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  • Matthies, Brent (Helsingin yliopisto, 2016)
    The ecosystem service (ES) approach is a means of evaluating service value flows from ecosystems to humans for their well-being. The approach suggests that ecosystem functions are divided into categories according to the benefits derived and utilized by beneficiaries. The ES approach has become a tool for public and private decision-makers, driven by the need to more accurately incorporate environmental externalities into the value creation processes of economic actors. This research addresses two knowledge gaps within the ES literature. First, a service-centric approach to ES offerings is lacking, resulting in misuse of the appropriate concepts and terms when discussing their role in value networks and value creation. Second, there is limited available knowledge about how to efficiently internalize ES offerings within value networks. In the first article, a service-dominant value creation (SVC) framework, with supporting terms and concepts, was developed to guide interdisciplinary discussions about the role of ES offerings within value creation processes. The term value-in-impact was proposed as a means for discussing the trade-offs and impacts concerning ES offerings within those processes. The subsequent three articles addressed the following design aspects of Payment for Ecosystem Service (PES) schemes: (1) sensitivity to parameter inputs, (2) price volatility impacts on service providers, and (3) behavioural economic contributions. Consideration for trade-offs among ES offerings, and between ES offerings and economic objectives were also incorporated. The results indicated that the holistic accounting of ES indicators, to determine the optimal species mixtures, and uncorrelated ES price interactions, to determine the optimal allocation of forest for conservation, led to ecological and financial diversification benefits for service providers. Nudging service providers also led to more socially efficient ES provisioning. In each case, the proposed Ecosystem Service Expectation Value (ESEV) was used to more accurately describe the perpetual provisioning of multiple ES offerings on forestland.
  • Rozov, Stanislav (Helsingin yliopisto, 2016)
    The histaminergic neurons of the hypothalamus in conjunction with hypocretinergic cells, monoaminergic nuclei of the brainstem and basal forebrain centers, constitute the ascending arousal system that plays a pivotal role in maintenance of wakefulness state. It has predominantly inhibitory reciprocal connections to their sleep-active counterparts, which enables an efficient transition between wakefulness and sleep. In combination with the circadian clock and homeostatic regulation of sleep its forms a network that regulate the sleep-wakefulness cycle. Because of the complex organization, it becomes difficult to estimate the significance of the crosstalk between the individual components of this regulatory network. Therefore, we focused on examination of interactions between the histaminergic system, the circadian and homeostatic components. We used electroencephalography in combination with behavioral analysis to quantify changes in spontaneous locomotion, wakefulness, non-rapid eye movement sleep and rapid eye movement sleep stages in response to an alterations of pacemaker rhythm. The shortening of the light-dark cycle led to re-distribution of these parameters towards aperiodicity, as well as increased sleep propensity, diminished daily rhythms of power of high θ-, and γ-waves, which are characteristic of an active wakefulness state as well as strengthened the phase-amplitude coupling between these frequencies. We used in vivo microdialysis in combination with sleep deprivation to understand the histaminergic regulation of homeostatic sleep propensity. During 6-hours of sleep deprivation, the histamine release was upregulated and comparable to its level during wakefulness, whereas when the sleep deprivation ceased, the release of histamine immediately dropped to the baseline level. To assess the effects of circadian regulation on histaminergic neurons, we estimated the daily changes of activities of the key enzymes involved in the histamine metabolism, histidine decarboxylase and histamine-N-methyltransferase as well as diurnal profile of histamine release. The 24-hour rhythms of production and release of histamine and its metabolite, 1-methylhistamine were detected, whereas activities of the enzymes had no detectable diurnal rhythm. Histamine release was highly positively correlated with changes in the power of the θ-frequency range. In order to understand the possible role of the histaminergic regulation of circadian system functioning we utilized mouse strains that constitutively lack histamine 1 and 3 receptors. The lack of histamine 1 receptor had no effects on the circadian rhythm of spontaneous locomotion, but the knockout of the histamine 3 receptor resulted in a substantial reduction of free-running activity rhythm amplitude. The expressions of the core clock genes, Per1, Per2 and Bmal1, in the suprachiasmatic nuclei of the hypothalamus, the cerebral cortex and the striatum were not affected in these knockout models. Based on the acquired results we concluded that the circadian process may affect homeostatic regulation, thus indicating an interaction of these processes. The circadian regulation of the histaminergic neurons takes place mainly at the level of histamine accumulation and release. In contrast, alterations in histamine-mediated signal transduction caused only minor alterations in examined circadian rhythms. Finally, we could not find evidence of an involvement of the histamine in homeostatic regulation of sleep-wakefulness cycle.
  • Kallio, Katri (Helsingin yliopisto, 2016)
    All positive-strand RNA viruses replicate their RNA genomes in close association with cellular membranes. A great variety of cellular membranes are utilized by different viruses and those membranes are extensively modified to support viral replication and to protect the viral RNA from host cell defense mechanisms. Alphaviruses, including Semliki Forest virus (SFV), are positive-strand RNA viruses replicating their RNA on membranes derived from endosomal and lysosomal compartments. SFV induces small invaginations called spherules on plasma membrane and on endosomal membranes. Viral replication complex assembly, spherule formation and initiation of replication are carefully orchestrated events and are guided by specific sequence elements within the genomic RNA as well as by important enzymatic activities of nonstructural proteins (nsPs). The aim of this research was to study in detail how alphavirus replication complexes are assembled and to define the minimum requirements for spherule formation by using a plasmid-derived transreplication system mimicking SFV replication. The role of the genomic RNA in replication was deciphered by using RNA templates, which were either modified or differed in length. Use of RNA templates differing in length clearly showed that they define the spherule diameter suggesting that the template has a significant role in spherule formation. By modifying or deleting specific sequences from the template it was shown that highly conserved RNA elements are important for SFV replication and do not tolerate modifications without compromising replication. Study with the nsPs of SFV showed that the enzymatic activities essential for virus replication are also needed for spherule formation and that enzymes like helicase, protease and polymerase are absolutely essential for replication. Membrane association of the replication complex is also required to establish virus replication in the cells. The work with mutated nonstructural proteins and modified templates revealed a clear correlation between the minus-strand synthesis and spherule formation. This work describes the alphavirus replication processes in detail and provides new principles, which may be generally applicable to study the positive-sense RNA virus replication and the formation of virus-induced membranous replication spherules.
  • Anyan, James (Helsingin yliopisto, 2016)
    This study explores how opportunities for higher education (HE) are distributed in Ghana's public universities to students; and particularly, how those from the disadvantaged sections of the Ghanaian society fare in that regard. It was approached as a multi-level (integrating elements of micro, meso and macro) and multi-perspective dual transformative case study. Drawing mainly upon data collected from semi-structured interviews with students, graduates, university officials and policy-makers, as well as secondary data archived by the relevant institutions; it examines the processes and patterns in the distribution of admission slots to students. It engages with the tensions and dilemmas confronting the universities in such allocations, and debates same, in the context of procedural justice and meritocracy on the one hand, and distributive justice and affirmative action on the other. The interactions and intersections of socio-economic and other significant variables parental education, family income, geographical location, gender and disability are discussed, principally, in the framework of effectively maintained inequality (EMI), to understand the factors influencing the patterns of distribution observed. The data were thematically analysed using both sensitising concepts from the literature review, the conceptual frameworks as well as the indigenous concepts that emerged from the data. The findings indicate that the distribution of HE seats in the two public universities selected for the study is highly inequitable with students who graduated from the few urban-based and elite upper secondary schools overrepresented while graduates from the majority rural-based and resource-poor schools are underrepresented. Although there was unanimity among the different groups of participants about the existence and persistence of the problem, their approaches to dealing with the problem proved dichotomous. While students from the rural schools, for instance, exposed their status frustration and assumed a reformist stance on the issue of remodelling the current grade-based admission system to one cognisant of the difficult circumstances under which rural students pursue their upper secondary education, their counterparts from the elite schools essentially defended the maintenance of the status quo. The majority of female participants, contrary to the views of policy-makers, strongly objected to affirmative action for the admission of females; arguing that the policy reinforces the notion that they are inferior to their male counterparts. The results further reveal a multi-layered social stratification in access to, and equity in HE in Ghana. Almost all the students and graduates who were admitted into the universities on affirmative action basis identified themselves as rural people from low-income families, with little or no parental education, and poor parental occupations. Such students, though in dire financial straits, were contrary to expectations, found to be very resilient and highly motivated to complete their studies; posting excellent academic performance. Students with disabilities were also found to be internally excluded, facing life and academic threatening challenges, whereas female students reported entrenched socio-cultural norms impeding the education and aspirations of women in the Ghanaian society. Against these backdrops, the study calls for a rethink of the current overly meritocratic admission procedures in Ghana's public universities that do harm to access and equity for the majority rural students. It further recommends financial support from government to support the affirmative action initiatives of the public universities; an improvement in the conditions of students with disability, and multi-sectoral interventions to ameliorate the barriers impeding the education of females. The successful completion of HE holding all things constant by these disadvantaged groups, with its attendant better educated citizenry, enhanced civic consciousness, empowerment and participation, in addition to other socio-economic benefits, make such investments worthwhile. Keywords: distributive justice, procedural justice, affirmative action, gender, disability, stratification.
  • Söderholm, Sandra (Helsingin yliopisto, 2016)
    Phosphorylation is one of the most important post-translational modifications of proteins. Phosphorylation is a rapid and reversible way of modifying proteins; it is involved in the regulation of many cellular processes, serving as the main transducer of intracellular signaling cascades. It is possible to identify thousands of protein phosphorylation sites from a single sample with mass spectrometry (MS)-based phosphoproteomics. This is the main reason why MS-based phosphoproteomics is such an excellent method for revealing global changes in phosphoproteomes. Computational analysis of the MS data is vital for identifying the proteins and post-translational modifications. The data analysis steps in the phosphoproteomics workflow are also crucial for biological interpretation, e.g. identifying activated kinases and kinase substrates, as well as unravelling signaling pathways and networks. Cells of the innate immune system are central players in the host defence against pathogens such as viruses. Their pattern-recognition receptors (PRRs) recognize pathogen-associated molecular patterns (PAMPs), which are conserved structures present in pathogens. The most important PAMPs in viral infections are the viral genomes and replication intermediates, and their detection evokes pro-inflammatory and antiviral responses in the infected cell. Host factors and signaling cascades that promote or inhibit virus infections can serve as potential drug targets. Since protein phosphorylation is vital for the progression of nearly all signaling cascades, there is an increasing interest in applying phosphoproteomics and combining it with bioinformatics in studying the regulation of cellular signaling under various conditions, including viral infections. The main aim of the studies included in this PhD thesis was to characterize the global changes in the cellular phosphoproteomes of virus infected and dsRNA stimulated innate immune cells, and to identify the host proteins and cell signaling pathways involved in the early stages of the host response to Sendai virus (SeV), influenza A virus (IAV), and viral dsRNA. A computational analysis tool, named PhosFox, was developed for processing and comparing MS-based phosphoproteomic data generated by multiple database search algorithms. PhosFox was used for cross-sample comparisons of phosphopeptide identifications. PhosFox also facilitated the identification of those proteins whose phosphorylation was different between samples, and the clarification of phosphorylation sites not described in the literature. The findings from the phosphoproteomic data were explored further by implementing functional studies involving small interfering RNAs (siRNAs) and kinase inhibitors. There were extensive alterations in the phosphorylation of proteins in human epithelial cells and macrophages that were transfected with the synthetic dsRNA-mimic polyinosinic:polycytidylic acid (pI:C) or infected with SeV or IAV. Many of these proteins were determined to be members of pathways with little or no previously known role in the antiviral response to these particular viruses and viral PAMPs. Two novel host factors, RelA-associated inhibitor (RAI) and sirtuin 1 (SIRT1), were identified as negative regulators of dsRNA-induced apoptosis and NF-κB regulated cytokine expression by combining 14-3-3 interactome and phosphoproteome characterizations. The p38 mitogen-activated protein kinase (MAPK) signaling pathway was found to be regulating cytokine expression and apoptosis in dsRNA-transfected human keratinocytes. MAPK signaling pathways were also regulated in SeV and IAV infected cells. The mTOR signaling pathway was shown to be critical for the interferon response and virus replication in SeV infected human lung epithelial cells. A substantial number of those cellular proteins whose phosphorylation status changed after SeV or IAV infection or viral dsRNA challenge were involved in Rho GTPase signaling. Major changes in protein phosphorylation in IAV infected primary human macrophages were linked to cyclin-dependent kinases (CDKs). CDK activity was shown to be required for efficient viral replication and host response in IAV infection. Administration of one specific CDK inhibitor, SNS-032, also protected mice from IAV-induced death. The studies included in this PhD thesis are some of the first to apply phosphoproteomics for characterizing host-virus interactions. They emphazise the benefit of applying phosphoproteomics and bioinformatics in innate immunity and viral research, i.e. it is possible not only to identify cell signaling pathways, but also the specific host factors that regulate the cellular responses to viral infections. The results of these studies underline the importance and the potential MS-based phosphoproteomics has in the discovery of novel host factors, which can serve as possible antiviral drug targets. In conclusion, the MS-based phosphoproteomics approach led to the discovery of novel host factors and cell signaling circuits in virus infected innate immune cells.
  • Koivisto, Juhani (Helsingin yliopisto, 2016)
    The dissertation Amenability of metric measure spaces and fixed point properties of groups consists of three articles revolving around amenability and property (T) in different contexts, and a summary. In the first article, (non-)amenability of hyperbolic metric spaces is considered. In it, we prove that a uniformly coarsely proper hyperbolic cone of a connected bounded metric space containing at least two points is non-amenable. In particular, this implies that any uniformly coarsely proper visual Gromov hyperbolic space with connected boundary containing at least two points is non-amenable. In the second article, the degree of amenability of metric measure spaces is considered in general. Here, we prove a homological characterisation of global weighted Sobolev inequalities for quasiconvex uniform metric measure spaces that support a local weak (1,1)-Poincaré inequality using methods from large scale algebraic topology. Returning to the topic of the first article, we show that a quasiconvex visual Gromov hyperbolic uniform metric measure space that supports a local weak (1,1)-Poincaré inequality with a connected boundary containing at least two points satisfies a global Sobolev inequality. In the third article, fixed point conditions for uniformly bounded group actions on Hilbert spaces are considered. In the article, we establish a spectral condition for the vanishing of the first cohomology group of the complex of square integrable cochains twisted by a uniformly bounded representation of an automorphism group of a 2-dimensional simplicial complex. In particular, if the automorphism group acts properly discontinuously and cocompactly on the complex this implies that every affine action of the automorphism group on the Hilbert space with linear part given by the representation has a fixed point. In the summary, the results of the articles are further explained and placed in a larger context: mathematically as well as historically.
  • Mäkelä, Johanna (Helsingin yliopisto, 2016)
    Neurodegenerative diseases are characterized by the progressive loss of structure and function of neurons, but the underlying mechanisms for this are largely unknown. Disturbed cell signaling and protein metabolism as well as mitochondrial dysfunctions are thought to be involved in several neurodegenerative diseases. Mitochondria are the major source of energy in the cell, and they also regulate cell death. In brain, neurons are highly dependent on oxidative energy metabolism. Mitochondrial dysfunctions cause oxidative stress with an excess production of reactive oxygen species (ROS). In neurodegenerative diseases such as Parkinson s disease (PD), ROS are thought to contribute to the loss of dopaminergic neurons in substantia nigra pars compacta (SNpc), which leads to dopamine depletion in striatum. Peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) is a transcriptional co-activator that regulates mitochondrial biogenesis, ROS defense and respiration. The lack of PGC-1α has been shown to increase the sensitivity of neurons to oxidative stress and brain injuries. In this study we show that increasing the expression of PGC-1α protects against toxin-induced oxidative stress in dopaminergic neurons. We show that PGC-1α expression in dopaminergic neurons can be modulated by resveratrol (RSV), fibroblast growth factor 21 (FGF21) and peroxisome proliferator-activated receptor γ (PPARγ) that are known to regulate metabolism in other tissues. The increase in PGC-1α expression and activation was linked to metabolic changes mimicing low energy levels in the cell, and an increase in SIRT1, a metabolic regulator sensing changes in energy levels. PGC-1α activation was further associated with an increase in mitochondrial respiration and antioxidant levels suggesting that the neuroprotective effect of PGC-1α was due to an improved capacity to combat oxidative stress. These results show that regulation of metabolism by PGC-1α activators could be a useful tool to prevent neurodegeneration in PD. In addition to modulating PGC-1α, RSV was also found to increase the expression of dopamine transporter (DAT) in dopaminergic neurons of female mice. The increase in the level of DAT increases the uptake of dopamine, further indicating that RSV has beneficial effects in dopaminergic neurons. By affecting DAT, RSV also contributes to maintaining functional neurons, as a decline in DAT has been associated with degeneration of dopaminergic neurons. This effect on DAT expression was mediated by estrogen receptors, indicating that the effect of RSV differs between genders that should be considered if RSV is used as therapy for patients with PD.
  • Äyräs, Outi (Helsingin yliopisto, 2016)
    Background: Increased nuchal translucency (NT) has been used as a screening method for fetal aneuploidies since 1990s. It is also known to be associated with a wide variety of structural defects and genetic syndromes. Long-term studies with a large cohort about the neurodevelopmental outcome of euploid children with increased fetal NT are sparse and the neurodevelopment is worth further study. Aim: The primary aim of this study was to collect data on the pregnancy outcomes, long-term neurodevelopmental and overall outcomes in a large cohort of fetuses with increased NT from singleton pregnancies in order to improve parental counselling. Material: All singleton pregnancies referred to the Department of Fetal Medicine at the Helsinki University Hospital due to increased NT in the first-trimester screening during 2002 2007 were studied. The outcome data were retrieved from hospital databases and national registers. Results: There were 1063 fetuses with increased NT in the first-trimester screening. Abnormal karyotype was observed in 224 fetuses (21%) and adverse pregnancy outcome occurred in 322 (30%). Termination of pregnancy was performed in 209 (20%) and there were 43 (4%) miscarriages and perinatal deaths. Of the 834 euploid fetuses 74 (9%) had structural defects or genetic disorders. Favourable pregnancy outcome became less likely by increasing NT: favourable outcome occurred in 92% in the lowest NT group (95th percentile 3.4 mm) and in 18% in the highest NT group (≥ 6.5 mm). Of the euploid fetuses with normal second-trimester ultrasound examination 96% were healthy at the discharge from the delivery hospital. During the follow-up (mean 6.5 years) neurodevelopmental impairment was detected in 29 (4.2%) and it was severe in 12 (1.7%). Major structural defects, severe neurodevelopmental impairment, or genetic disorders were detected in 54 cases (7%). Conclusion: One in five fetuses with increased NT (≥ 95th percentile) has chromosomal abnormalities and one in ten of the euploid fetuses has structural defects or genetic syndromes. Major health impairment (major structural defect, severe neurodevelopmental impairment, or genetic syndrome) is likely to be detected in 7% of euploid children with increased NT in the first-trimester screening but normal findings in the second-trimester screening. These results are helpful in counselling the parents when increased NT is detected.
  • Toivonen, Marjaana (Helsingin yliopisto, 2016)
    Environmental fallows are fields that aim to produce environmental benefits instead of agricultural products. In many European countries, the establishment and management of fallows is funded via agri-environmental programmes. This thesis focuses on the biodiversity benefits of environmental fallows in boreal farmland. I examined the impacts of different fallow types and landscape structure on the diversity and species composition of multiple taxa in fallows. I also aimed to evaluate what fallow types, and in what landscape context, are needed to contribute to different biodiversity objectives: the promotion of conservation concern species, overall species diversity or ecosystem services. Species richness and composition of the studied species groups differed substantially between fallow types, and landscape context further modified the value of fallows. Perennial fallows sown with meadow plants supported high plant species richness and bumblebee abundance. Old grassland fallows benefitted both butterflies in general, and butterflies and bumblebees with narrow niches and low dispersal capacities. The positive impacts were emphasized when long-term fallows were located in complex landscapes. High forest cover in the surrounding landscape increased plant species richness in perennial fallows. The breeding density of open farmland birds was highest in short-term meadow fallows in landscapes rich in perennial grasslands. Foraging edge birds preferred short-term meadow fallows in open landscapes and long-term grassland fallows in forested landscapes. Vegetation of annual fallow types game fields and landscape fields differed considerably from perennial fallows and other non-crop biotopes, thus enhancing landscape heterogeneity. My results show that the biodiversity benefits of fallows can be enhanced by adapting fallows to the landscape context and to specific conservation objectives. If the objective is to support species of conservation concern, managing long-term fallows in complex landscapes rich in perennial grasslands is probably the best strategy. Overall biodiversity can also be enhanced in short-term fallows, especially if they are sown with diverse seed mixtures of species that are not too competitive in field conditions. Depending on the sown species, short-term fallows provide good possibilities to enhance landscape heterogeneity and promote ecosystem services. Future studies should consider the specific roles of forest and perennial grasslands in driving the effectiveness of agri-environment schemes. In addition, the impacts of agri-environment schemes, including fallows, on realized ecosystem services should be investigated.
  • Mikeshin, Igor (Helsingin yliopisto, 2016)
    This thesis is the study of a rehabilitation ministry for the addicted people called Good Samaritan, run by the Russian Baptist Church. The study scrutinizes a two-dimensional process of Christian Rehabilitation. This process consists of two aspects: bodily detoxication through prolonged isolation, and radical moral transformation through conversion to Christianity. This twofold process corresponds to the twofold nature of substance use dependence: biochemical and psychological. The narrative of conversion is constructed upon the literalist reading of the particular translation of Scripture Russian Synodal Bible impacted by the 16th (Martin Luther) and 17th century (Jacobus Arminius and the Remonstrants) Protestant dogmatics and Russian historical and sociocultural context. The narrative of rehabilitation is also impacted by the street, junkie, and prison experience of the rehabilitants and their elders, who hold the authority to interpret Scripture. My research contributes to the study of Russian Evangelical Christianity and substance use dependence, both of which are unique and substantially influenced by contemporary Russian historical, sociocultural, political, economic, and linguistic context. At the same time, both Russian Evangelicalism and substance abuse share global features of Evangelical Christianity and drug epidemics. My analysis is based on the ethnographic fieldwork conducted from January 2014 to January 2015 in St. Petersburg and Leningradskaia oblast', Russia. The participant observation included prolonged stays in three rehab facilities, guest and missionary visits, church services, seminars, festivities, and extensive study of Protestant Christianity and substance abuse.
  • Aurela, Minna (Helsingin yliopisto, 2016)
    Atmospheric aerosols have a significant effect on people and the environment. They cause adverse health effects especially for cardiorespiratory patients. Atmospheric aerosols also affect the Earth s climate directly by scattering and absorbing solar radiation and indirectly by modifying amounts and properties of clouds. Reliable characterisation and quantification of airborne particles and their sources are essential for developing control strategies for atmospheric pollution and decreasing the uncertainties of estimating particles effects on climate change. Aerosols can be divided into fine and coarse particles based on their size. This thesis concentrated on fine particles, which are either directly emitted into the atmosphere (primary particles) or formed in the atmosphere through gas-to-particle conversion (secondary particles). The main sources of atmospheric fine particles are natural and anthropogenic combustion, industry and secondary aerosol formation (biogenic and anthropogenic). The overall objective of this thesis was to investigate the chemical composition of fine particles with different temporal and seasonal time-scales. For this purpose, a variety of different sampling techniques, off-line analytical methods and on-line instruments were used to characterise the main chemical species of fine particles in simultaneous and independent campaigns at several sites mainly in southern Finland but also in South Africa. More specific objectives were to investigate the dominant sources of particulate organic matter in the Helsinki area and chemically characterise the fine particles originating from biomass burning. Determining the effect of air mass origin on the chemical composition and concentration of fine particles was also one of the specific aims. In this thesis, it was found that the chemical composition of fine particles had strong spatial and temporal variation, although on average the mass concentrations of fine particles were quite similar between different sites. The main components in fine particulate matter in southern Finland was particulate organic matter (POM), followed by sulphate, whereas sulphate had the highest contribution to particulate mass in South Africa. Source apportionment analysis of POM revealed clear primary sources from traffic and from biomass burning. However, the secondary organic aerosol had the largest contribution of POM, even though the campaigns were conducted in specific environments such as residential areas where biomass combustion is commonly used or traffic environments. Occasionally, the contribution of biomass burning organic aerosol increased substantially as ambient air temperature decreased. Additionally, simultaneous measurements pointed out a high contribution of common regional or long-range transported sources over large areas of southern Finland. Similarly, the air mass passing over either clean or polluted areas showed a significant effect on the mass concentrations in Finland and South Africa.
  • Etongo Bau, Daniel (Helsingin yliopisto, 2016)
    Tropical deforestation and forest degradation (DD) contribute approximately 15% of the annual global anthropogenic greenhouse gas (GHG) emissions. However, they are considered the main emissions sources in most developing countries. Despite the potentials of forest and tree plantations to mitigate the effects of climate change through carbon sequestration, DD still remains a challenge in Africa. Globally, the forests of Africa are the most depleted of all tropical regions, with only 30% of historical forest area still remaining. In addition, Africa s complexity in terms of its geography, politics, socioculture, economy, institutions etc. is an indication of why Africa has defied all simple solutions in addressing DD: a phenomenon considered location- and situation-specific. The biophysical setting of Burkina Faso exposes the central and northern region to drought and desertification. Such conditions have caused human migration to the southwestern regions, which offer better opportunities for rain-fed agriculture, but also experiences the highest rates of deforestation. On the other hand, the ongoing regreening process in the Sahel through tree planting and assisted natural regeneration of indigenous tree species is a signal for regrowth and revegetation. This study contributes to understanding the drivers of DD in four adjacent village communities in the Ziro province, southern Burkina Faso in the light of the forest transition theory. Specifically, this study assesses the drivers of DD at the farm/forest level and also identifies options for regrowth/revegetation. This dissertation consists of four articles (studies I, II, III, and IV). Studies I and II refer to stage two of the forest transition curve (forest frontier) while studies III and IV refer to stage four of the curve (forest/plantations/agricultural mosaics). Various methods were used during data collection, including interviews with key informants, focus group discussions (FGDs), two hundred household interviews (studies I, II, and III), gathering a list of local botanical knowledge from 48 participants (study IV), and a field survey. Qualitative and quantitative methods were used in analyzing the data. Low agricultural production expressed in the sizes (areas) and ages of farms together with land tenure insecurity were found to lead to increased deforestation. Results suggested that a 10% increase in farm size would result in a 4% increase in annual deforestation (study I). Furthermore, results in study II indicated that non-poor and fairly poor farmers contributed more towards activities considered environmentally degrading, such as deforestation, overgrazing etc., than the poorest farmers. On the other hand, the adoption of sustainable land management practices was relatively low among the poorest farmers. Tree planters were mainly farmers who held large and old farm areas, were literate and relatively wealthy, held favorable attitudes towards tree planting, and had participated in a farmers group for several years (study III). Local knowledge of tree species was found to be unevenly distributed in relation to gender, age, ethnic group, and location. Plant species assigned relatively high use-values for livelihood include Adansonia digitata, Parkia biglobosa, Vitellaria paradoxa, and Balanites aegyptiaca. On the other hand, Adansonia digitata, Tamarindus indica, and Ficus thonningii were considered more important for environmental protection (study IV). The dissertation concludes that tenure insecurity and low agricultural production contribute to DD at the farm/forest level on the one hand while tree plantations, land management practices, such as fallow, zai pits (a traditional soil and water conservation technique), and assisted natural regeneration of indigenous tree species are important activities promoting regrowth/revegetation.
  • Mathijssen, Paul (Helsingin yliopisto, 2016)
    Peatlands contain approximately a third of all soil carbon (C) globally and as they exchange carbon dioxide (CO2) and methane (CH4) copiously with the atmosphere, changes in peatland C budgets have a large impact on the global C balance and on the concentration of greenhouse gases in the atmosphere. How peatlands will react to future climate changes, however, is still relatively uncertain and as such there has been a growing interest in the reconstruction of past peatland C dynamics and linking these to past climate variations. In order to increase the understanding of peatland development and response patterns, I quantitatively reconstructed the Holocene (the last c. 11700 years) C dynamics of three different peatlands in Finland: a subarctic rich fen, a boreal poor peatland complex and a boreal managed pine bog. Several cores from each peatland were studied in order to reconstruct peatland succession, lateral expansion, peat and C accumulation rates, long term uptake of atmospheric CO2, CH4 fluxes and radiative forcing (RF). Peatland lateral expansion was most rapid during periods with relatively cool and moist climate conditions. The peatlands showed distinct successional pathways, which were sometimes triggered by fires. Successional stages were partly reflected in C accumulation patterns. In some cases, variations in C accumulation rates coincided with autogenic changes in peat type and vegetation, although accumulation rates were also related to the large-scale Holocene climate phases. The warm and dry conditions during the Holocene Thermal Maximum (between c. 9000 and 5000 years ago) reduced C accumulation rates in the subarctic fen and the boreal peatland complex. Reconstructed CH4 emissions suggest that CH4 emissions played a major role in the total C budget of the peatlands throughout the Holocene. The RF models based on long term CO2 uptake and CH4 emissions showed that the two boreal peatlands had a warming effect on the atmosphere for the first 4000-7000 years after the start of peat accumulation, after which they had an increasing cooling effect as a result of the long term effect of C uptake and storage. In contrast to the two southern sites, the subarctic fen had a warming effect through its entire history as a result of very low C accumulation rates. The results of my study show that peatland processes react differently to allogenic factors, such as climate and fire, depending on peatland type, microtopography and local hydrology. It highlights the necessity to study multiple peat cores per site before making exhaustive conclusions on historical development patterns and implications. The combination of lateral and vertical peat growth data with reconstructed CO2 and CH4 fluxes provided the necessary information for a comprehensive quantification of the climate - peatland feedback. In the studied sites this feedback seemed to be very sensitive to short term variations in CH4 emissions and lateral expansion.
  • Kaatrakoski, Heli (Helsingin yliopisto, 2016)
    In the public sector, an emphasis on a customer approach has spread to a number of fields of work in Finland. This thesis investigates the conveyance and development of the concept of customer in four Finnish public organisations. The point of departure for the study is the marketisation of the public sector and the New Public Management (NPM) ideology, which emphasise the benefits of business models in public sector practices. The introduction of the concept of customer is an example of such benefits, and the development of the concept is examined in this particular cultural and historical context. Previous international studies have raised challenges related to customer thinking in the public sector and concerns over official discourses that seem to simplify the fundamental societal implications produced by the customer approach. The theoretical framework of my study is cultural-historical activity theory. The data comprises interviews (53) and documents (42) from each organisation. The studied organisations represent fields of elderly care, children s day care, road management, and academic library work. The findings in the document analysis suggest that in all the studied organisations, the use of the concept of customer has increased along with the introduction of the NPM doctrine. One interesting finding is the variety of conflicting situations which the interviewees experienced regularly in their service encounters. These conflicting situations are related to dominating old organisational structures and practices, which have not developed sufficiently with regard to customer thinking. In addition to these conflicting situations, another interesting finding was shared discourses which were related to the customer approach. My interpretation in this study is that at the core of the concept of the public sector customer are the opposing forces of the private sector s understanding of human beings as responsible individuals with free choice and the public sector s emphasis on collective citizenship and the public good. The opposing forces produce not only a variety of conflicting situations, but also possibilities for the development of the concept. This thesis theoretically opens up the background ideology behind the concept of customer in the public sector and thus increases the understanding of larger ongoing societal changes. The study provides new openings in regard to empirical studies on customer thinking from the perspective of employees. Such research objectives have been limited in number in the Finnish context. One important contribution of this study in regard to studies of working life is its explanation of the origin of conflicting situations from systemic tensions instead of trying to trace their origins to the behaviour of individuals.
  • Howlader, Mohammad Sajid Ali (Helsingin yliopisto, 2016)
    Amphibians are the most threatened class of vertebrates. About 48% of the known amphibian species are threatened by extinction, and many species still remain undescribed, especially from tropical and sub-tropical countries such as Bangladesh. In contrast to India and Sri Lanka, amphibian diversity in Bangladesh is poorly known, and little effort has been put towards documenting the species diversity and resolving evolutionary affinities among amphibian taxa in this country. Hence, the actual diversity of amphibians in Bangladesh remains unknown. The aim of this dissertation work was to improve our knowledge of amphibian diversity in Bangladesh by identifying and describing new amphibian species and investigating their evolutionary relationships with closely related taxa. I used morphological and molecular phylogenetic methods to identify and describe one new genus and five new species from different genera. In addition to using traditional morphological comparisons, I also utilized mitochondrial gene fragments to estimate phylogenetic affinities among the studied taxa, with Maximum-likelihood and Bayesian methods. The first two chapters of the thesis focus on the amphibian genera Fejervarya and Zakerana, the latter which was previously embedded within Fejervarya. These chapters also include descriptions of two new species Fejervarya asmati sp. nov. (now Zakerana asmati), as well as Fejervarya burigangaensis sp. nov. , respectively. In the third chapter, a new species (Zakerana dhaka sp. nov.) is described from the urban core of Dhaka, the capital of Bangladesh and one of the most densely populated mega cities in the world. In the fourth chapter, I describe Euphlyctis kalasgramensis sp. nov., which was earlier recognized as E. cyanophlyctis, and show that it is genetically highly divergent from the E. cyanophlyctis described from southern India. In the last and fifth chapter, I describe Microhyla nilphamariensis sp. nov. as a new species. It is a member of a highly genetically heterogeneous group of frogs that have been recognized as M. ornata for the past 173 years. In general, the results of the studies included in this dissertation advance our understanding of amphibian diversity in Bangladesh and adjacent regions, and show that discovery and description of new amphibian species from this region is still fairly easy. Consequently, it seems likely that more thorough sampling and further investigations in this region can uncover additional new amphibian species to science. Such studies, together with the discoveries described in this thesis, should also provide useful information for understanding and conserving the amphibian biodiversity in this poorly studied region.
  • Karikoski, Ninja (Helsingin yliopisto, 2016)
    Laminitis is a common, debilitating condition of equids that may have substantial effects on animal welfare. Laminitis may be related to endocrinopathic or inflammatory diseases, as well as uneven weight distribution. Until recently, research into the prevalence of endocrine disease amongst horses with laminitis has been overlooked, although it was anecdotally thought to be high. Most histological studies have been conducted on experimental carbohydrate overload or inflammatory models. However, more recently the histology of a hyperinsulinaemic model of laminitis was described with important differences apparent from the previous inflammatory models however, a more detailed study had not been performed. Furthermore, the histology of chronic, naturally occurring endocrinopathic laminitis has not been described and compared to that of healthy animals. The research presented in this thesis aimed to investigate endocrinopathic laminitis. In Study I, the prevalence of endocrine disease (either basal hyperinsulinemia or pituitary pars intermedia dysfunction, PPID) among horses that presented for laminitis at a first-opinion/referral equine hospital was shown to be 89%. In Study II, secondary epidermal lamellar elongation, narrowing and alteration in orientation were shown to be largely attributable to cell stretching in ponies with insulin-induced experimental laminitis (rather than proliferation as had been hypothesised), that occurred at the same time as an accelerated cell death-proliferation cycle. In Study III, the histomorphometry and pathological lesions of endocrinopathic laminitis were shown to be largely localized abaxially within the lamellar tissue including increased lamellar length and width, chronic abnormal keratinization, interlamellar epidermal bridging and apoptotic cell death with more acute lamellar tearing in some cases. Additionally, in all the laminitis cases, there were macroscopic pathological changes (divergent rings on the outer hoof wall and/or rotation of distal phalanx). However, both lamellar and macroscopic pathology varied in severity and were unrelated to the reported duration of laminitis. In Study IV, PPID animals with and without laminitis were compared. All the laminitic PPID animals also had hyperinsulinemia whereas all of the non-laminitic PPID animals were normoinsulinemic. In addition, all the PPID animals with laminitis had histological lesions in the lamellar region, but the lamellae of PPID animals without laminitis were normal when compared to the control group. In conclusion, endocrinopathic laminitis is by far the most common type of naturally occurring laminitis in horses and hyperinsulinemia is likely to be the primary cause in those horses, including those with PPID. In the acute phase, the pathophysiology behind the key lesion, SEL elongation, is proposed to be cellular (mechanical) compromise resulting in epidermal cellular stretching. In the chronic phase, the lamellar lesions are variable in severity in many cases allowing for a prolonged subclinical phase, and they are located predominantly abaxially close to the hoof wall.
  • Airaksinen, Jaakko (Helsingin yliopisto, 2016)
    Differences in well-being between neighborhoods have long been recognized. These inequalities have been explained by neighborhood effects, in other words characteristics of the neighborhoods that affect well-being. However, the direction of causality in neighborhood effects is still unknown. This dissertation examines whether inequalities in well-being between neighborhoods are caused by neighborhood characteristics social causation, or by selective residential mobility social selection. The participants in these studies were from the ongoing prospective longitudinal population-based Young Finns study. The aims of this study were: 1) to examine whether neighborhood urbanicity and socioeconomic status affected health behaviors, depressive symptoms and source of social support, and 2) to examine how those variables affect residential mobility behavior. The results suggest that people in more urban and affluent neighborhoods are more interested in their health. However, simultaneously those people drink more alcohol, and also people in more urban areas smoke more. People in more rural areas received more social support from their family, whereas people in more urban areas received more social support from their friends. While part of the results were explained by social causation, most of the effects were attributed to social selection. People who received more social support from their friends were more likely to move and to move more frequently. Also, people with better health behaviors moved longer distances. None of the individual level variables were associated with selective residential mobility between municipalities. This dissertation addressed the problem of causality in neighborhood effects. The findings do give some support for social causation in neighborhood effects, but most of the effects are explained by social selection. However, the results also imply that health behaviors or social support do not affect selective residential mobility. Therefore, it is likely that some other individual level variables govern selective residential mobility and the forming of differences in well-being between neighborhoods.
  • Koskinen, Anni (Helsingin yliopisto, 2016)
    Background: Chronic rhinosinusitis (CRS) is a multifactorial inflammation of the nose and paranasal sinuses. It is diagnosed by typical symptoms lasting more than 12 weeks and/or a computed tomography scan (CT) and/or endoscopic changes. In Europe the prevalence of CRS has been found to be 10.9% 1. The treatment of CRS is primarily conservative, with nasal saline irrigations and topical intranasal corticosteroids. Antibiotics are used primarily only during exacerbations. Comorbidities such as asthma and allergy should be treated efficiently as they can predispose to CRS. Immunodeficiency can also be discovered behind CRS or vice versa. Especially defects in humoral immunity are thought to be more prevalent among CRS patients than healthy controls 2. If conservative treatment of CRS fails, surgery is indicated. Endoscopic sinus surgery (ESS) is a well-established strategy in the treatment of patients with CRS refractory to maximum medical therapy. During the last decade balloon sinuplasty has partly replaced ESS in the treatment of CRS. In balloon sinuplasty the natural ostium of the sinus is dilated without removing mucosa or bone. Methods: First we performed a retrospective controlled study in which we compared humoral immunity between chronic- or recurrent rhinosinusitis patients and healthy controls. Immune responses to tetanus and diphtheria vaccines were evaluated by measuring specific antibody levels of the serum samples of 25 CRS patients and 30 control patients. Next we performed a retrospective controlled study in which we compared ESS and balloon sinuplasty in the treatment of CRS. In this study 208 patients with CRS without nasal polyps underwent either balloon sinuplasty or ESS of maxillary sinuses. Forty-five ESS patients and 40 balloon patients met the inclusion criteria. These patients were sent a postal questionnaire approximately 28 months postoperatively. Patient history factors, number of exacerbations, and a visual analog scale (VAS) scoring the change in symptoms between preoperative and postoperative status were evaluated. We also analysed intra- and early postoperative factors, such as operation time, anesthesia method and complications among the same patients treated either with ESS and balloon sinuplasty. To investigate the long-term efficacy and satisfaction among these patients we performed a phone-interview on average six years after the primary surgery. Patients were asked to compare present symptom status with the symptoms before the operation. Number of exacerbations and need for revision surgery were also evaluated. Results: We were able to show that after vaccination patients with chronic- or recurrent rhinosinusitis had on average 4.08-fold lower responses to diphteria toxoid than healthy controls recruited from hospital personnel. Antibody levels to tetanus toxoid were on average 2.20-fold lower among CRS patients than in the healthy control group. Fourteen out of the 25 rhinosinusitis patients had antibody levels that did not reach the 95% normal distribution range of healthy controls after either diphteria or tetanus vaccination. In the retrospective study comparing ESS and balloon sinuplasty, the groups were identical in response rate and patient characteristics. The duration of sick leave was significantly longer in the ESS group. However, the duration of sick leave was only an estimate of the recovery time made by the operating surgeon and does not necessarily correlate to the true recovery time. Eight ESS operated patients were detected with adhesions, as no adhesions were found in the balloon sinuplasty group. In the first questionnaire study, patients in both groups experienced equal improvement of all asked symptoms. The balloon sinuplasty group reported a statistically significant higher number of maxillary sinus punctures and antibiotic courses during the last 12 months. According to the phone-interview study, enrolled approximately six years after the primary operation, both groups experienced improvement in all symptoms and were equally satisfied with the operation. The number of patient-reported acute exacerbations was again higher among the balloon dilated patients. Four patients in the balloon sinuplasty group underwent revision surgery. There were no revisions in the ESS group. These findings were statistically significant. Conclusion: A significant proportion of our study patients had reduced antibody responses to protein vaccines. This could indicate that CRS patients might have impaired humoral immunity predisposing them to chronic and/or recurrent infections. Responses to protein vaccines might be used to evaluate immune status of CRS patients. Results of our study comparing ESS and balloon sinuplasty showed that the techniques seemed comparable in terms of operation time, anesthesia method and low complication rate. The putative benefits of balloon sinuplasty might be lower adhesion formation, shorter recovery time and possibility to be performed in-office. Except the increased number of revisions in the balloon sinuplasty group, both techniques seemed to retain the efficacy and patient satisfaction in average two and six years after the surgery. Patients in our study were carefully selected with neither nasal polyposis nor severe sinonasal pathology. This should be borne in mind when applying these results in clinical practise. The role of balloon sinuplasty in the management of CRS patients with nasal polyposis or more extensive disease needs to be established by further studies.
  • Venesjärvi, Riikka (Helsingin yliopisto, 2016)
    Maritime transport is an efficient way to ferry goods, oil, and chemicals but shipping poses a threat to marine ecosystems. Oil spills have a potential to extinguish or debilitate fish and wildlife populations and habitat types important to the marine ecosystem. In this thesis, I study the resources and methods for collecting data and knowledge about the adverse impacts of oil on sensitive species and habitat types. Furthermore, I study how ecological knowledge could be passed to decision-makers and how the risks should be communicated. Finally, I discuss future policy improvements and scientific needs for ecological knowledge in oil spill risk management. This forms a synthesis of what kind of ecological information is required for the environmental risk management and conservation of marine ecosystems under oil spill threat. The thesis includes five papers, where we develop methods to assess the environmental impacts of oil spills and the effectiveness of management practices to mitigate their adverse ecological effects. Improved strategies combine theoretical disciplines, such as population biology with practical oil spill response. The results demonstrate that environmental risk assessment models can be used to structure problems, integrate knowledge and uncertainty, and persuade decision-makers by visualizing the results. Since the objective of risk assessment is to synthesize information for environmental management and policy design, which should rely on the extensive use of scientific evidence, communication between academia and decision-makers is of great importance. The use of Bayesian networks would improve the current oil spill risk management in the Baltic Sea, since all the variables affecting oil spill risk can be presented in one framework in a transparent manner. Many geospatial services work as tools of informative policy instruments, as they deliver ecological data and knowledge for oil spill risk management. Researchers could also participate more often in the contingency planning or practical management of oil spills as experts. Thus, all the relevant knowledge could be integrated into the decision-making process. This thesis offers new insights into oil spill risk management in the Baltic Sea and provides examples showing how evidence-based management actions should be chosen and carried out in order to minimize the risks. Policy recommendations are also provided. First, in oil spill risk management, the marine ecosystem should be prioritized based on its conservation value, recovery potential and protection effectiveness. Second, because preventive measures against oil accidents are considered cost-effective, maritime safety should be increased, with stricter and regional ship inspection practices. The effects of policy innovations should be assessed using probabilistic policy-support tools.
  • Dudek, Mateusz (Helsingin yliopisto, 2016)
    Alcohol addiction is one of the most prevalent brain disorders in the world. A major hurdle for reducing alcohol-related harms and developing effective treatments is the poor understanding of neural processes responsible for the development of dependence and addiction. Alcohol has been shown to affect various neurotransmitter systems; however, the mesolimbic dopamine (DA) system, which projects from the ventral tegmental area (VTA) to the nucleus accumbens (NAc), has been thought to play a key role in producing the reinforcing effects of alcohol. The VTA region has also been suggested to be the anatomical site for the interaction of the dopaminergic system with the opioidergic and γ-aminobutyric acid (GABA) systems. Here, manganese-enhanced magnetic resonance imaging (MEMRI) and behavioral tests were used to study drug-induced alterations in brain activity of the alcohol-preferring AA (Alko Alcohol) and heterogeneous Wistar rats. MEMRI is based on the ability of paramagnetic Mn2+ ions to accumulate in excitable neurons, thus enhancing the T1-weighted signal in activated brain regions. Mn2+ ions can also be transported anterogradely and retrogradely in neurons, released to the synaptic cleft, and taken up by other neurons. These properties allow MEMRI to measure long-term changes in brain activity, as well as map neural pathways involved in acute and long-term drug actions, including drug reward and toxicity. The AA rats exposed to alcohol compared to water controls displayed a widespread and persistent activation in brain regions that have been previously linked with alcohol reinforcement. Similarly, activity in neural pathways originating in the NAc and projecting caudally to the midbrain was enhanced in alcohol drinking rats. Moreover, this alcohol-induced activation was blocked by systemic naltrexone (NLX) administration. Comparison of naïve AA and Wistar rats revealed a lowered basal activity in the caudal linear nucleus (CLi) of AA rats, which was restored by voluntary alcohol drinking. The intra-CLi γ-aminobutyric acid type A receptor (GABAA) agonist muscimol produced a dose-dependent increase in alcohol drinking, blocked by co-administration of the GABAA antagonist bicuculline, suggesting that the CLi GABAergic system is involved in the regulation of alcohol reward. MEMRI was also employed for assessing stimulant-induced toxicity. Methamphetamine and mephedron displayed disparate effects on brain activity, as methamphetamine produced widespread decreases in activity, whereas mephedron increased activity in limited brain areas. Taken together, the use of MEMRI for mapping alcohol- and stimulant-induced alterations in functional brain activity revealed networks and specific pathways that have potential for guiding further translational efforts to develop medications for drug abuse disorders, as well as for evaluating drug-induced toxicity.